and this won't be found as the URL "in-defense-of-yoga-pants-yogis-of-the-west-karen-macklin" doesn't exist in the database.

Is there a way to turn this stop function sanitize_title_with_dashes from getting run? without me having to hack the code of WordPress - otherwise this issue will appear again when we next get an update.

-switching to the unedited default theme (that came with your version of WP) for a moment by renaming your current theme's folder in wp-content/themes. The idea is to force WordPress to fall back to the default theme to rule out any theme-specific issue.

-If the above steps do not resolve the issue, download WordPress again and replace your copies of everything EXCEPT the wp-config.php file and the /wp-content/ directory with fresh copies. This should replace your core files without changing your content and settings in wp-config.php file and the /wp-content/ directory.